Adjustable support for tool frames on a lift type tractor



Dec. 23, 1952 N. J. HUGGER ADJUSTABLE SUPPORT FOR TOOL. FRAMES ON A LIFTTYPE TRACTOR 2 SHEETS--SHEET 1 Filed NOV. 2, 1950 NORBERT J Hues/5RGttorneg Dec. 23, 1952 N J. HUGGER ADJUSTABLE SUPPORT FOR TOOL FRAMES ONA LIFT TYPE} TRACTOR 2 SHEETS-SHEET 2 Filed Nov. 2, 1950 NORBERT dHUGGER Zmnentor Patented Dec. 23, 1952 UNITED STATES P TENT DFFICEADJUSTABLE SUPPORT FOR TOOL FRAMES oN A LIFT TYPE 'rneo'roa Thisinvention relates in general to a tool lift mechanism and moreparticularly to a type thereof applicable to :a tractor of the so-calledlift type for raising and lowering a tool frame pivotally secured to therear axle of said tractor and extending beyond the forward end thereof.

Tool frames of this type are conventionally used with tractors ofthese-called lift type, which type is illustrated in U. 5. Patents No.1,687,719, No. 2,118,180 and No. 2,118,181. The tool frames are used tomount ground Working tools, such as bull-dozer blades, on the forwardend of the tractor. In present support and lift mechanisms for suchframes, adapted for use with the lift type of tractor, the lifting forceis normally applied by cables, supported upon the tractor frame,forwardly of the front axle of the tractor for the purpose of obtainingthe maximum lifting effect with aminimum of force applied. However, thishas occasionally resulted in causing the tractor to rotateabout thefront axle and to lift the rear end of the tractor, when a greater thanusuallifting force is applied to the frame for the purpose, by way ofexample, of disengaging a tool, mounted upon said frame, from theground. In some cases said-cables are supported upon the frontaxle-whereby the vertical movement of the front wheels is translated tothe tool.

I have foundthat, by applying the lifting force to the tool frame at apoint intermediate the axles of the tractor, such raising ofthe rear endof the tractor is eliminated, and vertical movement of the tool isgreatly reduced. In. order to accomplish this end, I have conceived animproved tool lift mechanism which is hereinafter disclosed.

Accordingly, a primary object of this invention has been the provisionof a tool lift mechanism for a tool frame pivotallysupported upon therear axle of a tractor and extending beyond the forward end thereof,whereby therear end of the tractor does not tend to raisewhen force isapplied to lift the tool frame.

A further object of this invention. is to provide a tool lift mechanism,as-aforesaidwhich applies its lifting force to the tool frameat a pointintermediate the axles of the tractor.

A further object of this invention is to provide a tool lift mechanism,as-aforesaid, which can be operated from the conventional hydraulic toollift of a conventional tractor equipped therewith.

A further object of this. invention is to provide 2 Claims. (C1.Bile-50) ally operable a tool lift mechanism, as aforesaid, in which theparts thereof are easy to construct and can be mounted upon aconventional tractor having a hydraulic tool lift with a minimum ofeffort and skill. Y

Other objects of this invention will become apparent to those familiarwith this type of device by reading the followingdescription andexamining the accompanying drawings.

In the drawings:

Figure l is a side elevational view of my invention shown positionedon alift type of tractor.

Figure 2 shows the frame and lift lever as viewed from the line 11-41 inFigure 1.

Figure 3 is a sectional View taken substantially along the line IIIIIIof Figure 1.

Figure 4 is an enlarged top view of the lift lever.

Figure5 is an enlarged, broken, sectional view taken along line V-V' ofFigure 4.

For the purpose of convenience and without intending any limitations,the terms rearwardly and forwardly, as used herein, shall have referenceto the front and rear ends of the tractor as shown-in Figure l and theparts associated therewith. The terms upwardly and downwardly shall alsobe used in referring to the invention and parts thereof as positioned inFigure 1.

General description In meeting the above outlined objects, as well asothers incidental thereto, I have provided a lift mechanism I0, Figure1, having a rectangular tool frame ll pivotally securedto the rear axleof a standard lift type of tractor, said tractor including a shaft i6disposed adjacent, here above, said rear axle, meansfor controllablyrotating said shaft in either direction and manumeans for controllingsaid lastnamed means. A cam 13 is secured to said shaft l6. A lift leverit is pivotally supported upon the transmission housing of said tractorwith its rearward end engaging the cam l3. A rod I5 is pivotally securedat its lower end to said tool frame II, and its upper end is slidablyand resiliently engaged by said lift lever l t. 7

It is to be understood that in employing my tool lift mechanism If] on atractor, two sets of such mechanism are used, one on each side of thetractor. However, since they are identical with each other, my inventionwill be sufficiently disclosed by describing in' detail only one set ofsuch-lift-mechani'sm If). his understood that the tractor here employedfor the purpose of describin the operation of this invention is of 3 astandard commercial type and forms no part of this invention by itself.

Detailed description The tool frame II (Figures 1 and 2), which issubstantially rectangular in shape, is positioned beneath a standardlift type of tractor with its side members 22 and 22a pivotally secured,near their rearward ends, to the rear axle 26 of the tractor byconventional pivot means, such as pivot brackets I8 and Isa and aconventional 'comiecting pin.

The side members 22 and 22a and the rear end member 23 of the tool frameII are frequently constructed from steel tubing, preferably of about 4diameter; the forward end member I9, which extends beyond the forwardend of the tractor, is preferably a fiat steel plate having a pluralityof suitable openings 24 extending therethrough for attaching bulldozerblades or other earth working implements.

A counter-weight 23 is usually positioned at the rear end of the toolframe II and secured to the support elements 2| and 2Ia (Figure 2) byany conventional means.

The shaft I6 (Figures 1 and 4), normally mounting a lift arm I2, isrotatably secured upon the housing 25 of the tractor in a position par-"allel with and above the rear axle 26 of the tractor. The lift arm I2,which turns with the shaft 15, extends perpendicularly therefrom.

The details of construction of the shaft I6 and the means for actuatingit are not herein further described, inasmuch as such mechanism isconventional equipment on all standard lift type tractors and itsconstruction is well known.

The cam I3 (Figure 1) is secured to one end of said shaft I6 and in thisparticular embodiment has its greatest radius at its forwardmostportion. It conveniently comprises a curved piece of steel fixed at itsone end in any convenient manner, as by being stud bolted, to the hub ofthe lift arm I2 and extending forwardly therefrom. The radius of saidcam being greater than the radius of said hub, the cam will extend awayfrom said hub in its forward portion. Thus, the radius of said cam willbe at a minimum at its rearward end and it will increase progressivelytoward its forward end.

It will be recognized that this cam may be afiixed permanently in placesince its presence will not interfere with other normal uses of thetractor or with the operation of the lift arm I2.

The lift lever I4 (Figures 1 and 4) is pivotally supported intermediateits end points at a pivot point 28 on the tractor transmission housing25 above said tool frame and forwardly of said shaft I6 and issubstantially parallel with the lengthwise extent of the tool frame I I.As shown in Figure 1, the pivot point 28 is preferably spaced above thetool frame I I substantially the same distance as the shaft I6 is spacedabove the tool frame II.

The forward end 40 of the lift lever I4 has an opening 30 extendingvertically therethrough and said lift lever is bent outwardly slightlywith respect to the rearward end 4I thereof.

The rearward end of the lift lever I4 is bent downwardly slightly withrespect to the forward end 40 and extends rearwardly to a point directlybelow and adjacent the cam I 3.

A cam follower, here a steel roller, 34 is rotatably secured within therearwardmost end of the lift arm I4, by conventional means such as pin35. The roller 34 extends slightly above the upper surface of the liftarm I4 for engagement with the lower surface of the cam I3.

The rod I5 (Figures 1 and 5) is pivotally secured at its lower end tothe side member 22 of the tool frame II at a point 3| intermediate thefront and rear axle of said tractor in vertical alignment with theopening 30 in the lift lever I4. The upper end of the rod I5 extendsvertically upward through the opening 30 and is externally threaded atits uppermost end to receive the stop nut 32.

The rod I5 is of a diameter slightly less then the inside diameter ofthe opening 30 to allow the rod I5 to slide easily through the opening30. The nut 32, however, is of a diameter greater than the opening 30 soas to prevent downward movement of the rod I5 through the opening 33beyond the nut 32.

A spring 33 encircles the rod I5 between the lower surface of the liftlever I4 and the stop nut 32a so as to yieldably urge the lift lever I4against. the upper stop nut 32.

A U-shaped guide frame 33 (Figure 3) is constructed from any convenientmaterial, here one inch steel tubing. is secured to the front axle ofthe tractor by conventional rivets, or bolts, 45 and 45a and ispositioned between the side members 22 and 22a of the tool frame II. Theside members 46 and 46a of the guide frame 36 are positioned adjacentthe side members 22 and 22a and have a bearing strip 4! and 41a weldedto their outer surface. The bearing strips 41 and 41a are slidinglyengaged by the respective side members 22 and 22a when the tool frame IIis pivoted about the rear axle 26 of the tractor.

Operation In operation, when a tool, as a bulldozer blade 31 (Figure 1),is attached to the front plate IQ of the tool frame I I, the tool may beconveniently raised or lowered by simple manipulation of the hydrauliclift mechanism of the tractor.

When the shaft I6 is rotated counter-clockwise to its lowermost positionof the lift arm I2, as shown in Figure 1, that portion of the cam lowersurface having the shortest radius, thus the rearward portion, contactsthe steel roller 34 and the rearward end M of the lever arm I4 is in itsuppermost position.

As the shaft I6 is rotated in a clockwise direction to the uppermostposition of the lift arm I2, that portion of the lower surface of thecam having the greatest radius, thus the forward portion, engages thesteel roller 34 and the rearward end M of the lever arm I4 is depressed.

When the rearward end of the lever arm I4 is depressed, the forward end40 is pivoted upward and the rod I5 is lifted, which in turn lifts theforward end of the tool frame II.

The steel roller 34, which engages the lower surface of the cam I3,rotates with movement of the cam I 3, thus reducing friction between theengaging surfaces.

When the tractor is in operation, the'tool attached to the frame II willoftentimes bounce over an irregularity in the earths surface, which willin turn cause the tool frame II to bounce. Therefore, the rod I 5 hasbeen slidingly attached to the lever arm I4 and a spring 33 has beenprovided around the rod I5 to prevent undue bouncing of the. tool frameII.

The guide frame 36, which is secured to the front axle of the tractor,guides the upward and downward movement of the tool frame II between thefront wheels of, the tractor.

As pointed out above, the advantage of having the lifting forceintermediate the axles of the tractor is that raising of the rear end ofthe tractor is substantially eliminated. Further, a device of maximumsimplicity, but great durability, is here provided.

While it is necessary in this structure to apply more force to the toolframe I l to lift same from its middle than from its end, thisdisadvantage is overcome in the mechanical advantage derivable from thecam. The conventional counterweight 20 will also assist.

Although the above mentioned drawings and description apply to oneparticular preferred embodiment of this invention, it is not myintention, implied or otherwise to eliminate other variations ormodifications which do not depart from the scope of the invention unlessspecifically stated to the contrary in the hereinafter appended claims.

Iclaim:

1. Tool supporting and controlling mechanism for use with a lift typetractor, said tractor having a shaft parallel with and positionedadjacent its rear axle and having also means for controllably rotatingsame, the combination comprising: a rectangular tool frame includingspaced longitudinal members positioned parallel to the longitudinalextent of the tractor and extending forwardly of said tractor, includingtool supporting means connecting the forward ends of said longitudinalmembers and counterweight supporting means connecting the rearward endsof said members, means associated with said longitudinal members forpivotally supporting said frame member upon the housing of the rear axleof said tractor; a cam and means for attaching same to said shaft; alevel disposed substantially parallel to, and above, one of saidlongitudinal frame members, and means pivotally mounting said leverintermediate its ends onto the frame of the tractor, said lever havingmeans at its rearward end for engaging said cam; means connecting theforward part of said lever with said one of said longitudinal members ata point thereon longitudinally intermediate (1) the forward wheels ofthe tractor and (2) the point of attachment of said frame to the housingof the rear axle of the tractor; whereby rotative movement 6 of saidshaft will act through said cam to raise and lower the rearward end ofsaid lever and thereby raise and lower the forward end of saidrectangular frame.

2. Tool supporting and controlling mechanism for use with a lift typetractor, said tractor having a shaft parallel with and positionedadjacent its rear axle and having also means for controllably rotatingsame, the combination comprising: a rectangular tool frame includingspaced longitudinal members positioned parallel to the longitudinalextent of the tractor and extending forwardly of said tractor, includingtool supporting means connecting the forward ends of said longitudinalmembers and counterweight supporting means connecting the rearward endsof said members, means associated with said longitudinal members forpivotally supporting said frame member upon the housing of the rear axleof said tractor; a cam and means for attaching same to said shaft; alever disposed substantially parallel to, and above, one of saidlongitudinal frame members, and. means pivotally mounting said leveronto the frame of the tractor, said lever having means near its rearwardend for engaging said cam; means connecting a part of said leverforwardly of its point of engagement with said cam with said one of saidlongitudinal members at a point thereon longitudinally intermediate (1)the forward wheels of the tractor and (2) the point of attachment ofsaid frame to the housing of the rear axle of the tractor; wherebyrotative movement of said shaft will act through said cam to raise andlower the rearward end of said lever and thereby raise and lower theforward end of said rectangular frame.

NORBERT J. HUGGER.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,637,525 Huston Aug. 2, 19272,125,593 Starr Aug. 2, 1938 2,187,707 Kane Jan. 16, 1940 2,200,768Benjamin et al. May 14, 1940 2,313,534 Gledhill Mar. 9, 1943

